1. Field of the Invention
The present invention relates to a photomask manufacturing support system for carrying out a drawing data analysis and an inspecting data conversion of a semiconductor photomask and/or reticle.
2. Description of the Related Art
For manufacturing photomasks and reticles (hereinafter, generally referred to as “photomasks”) of semiconductor devices with a high yield, a pre-analysis of drawing data for photomasks and an observation and analysis of patterns on photomasks have become important. Results of these analyses are utilized as parameters to optimize finished drawing conditions of photomasks. When these analyses are not carried out, drawing device operation parameters are to be set empirically or by guesswork, which may considerably deteriorate the drawing yield.
However, recently, in semiconductor photomask manufacturing process, design data has been miniaturized as a result of miniaturization of semiconductor rules, and in accordance therewith, the data volume has become huge. Thereby, an influence of data processing time exerted on throughput has been increased. Therefore, the time required for a pre-analysis of drawing data and an observation and analysis of a photomask pattern has been extended long, this has exceeded a drawing time in some cases, which has caused an increase in operation costs.
In regard thereto, a technique for dividing a structure formed by breaking a hierarchical structure of photomask drawing data into a plurality of regions and carrying out hierarchical processing of pattern data contained in each region in a parallel distributed processing has been disclosed in Japanese Patent Application Laid-Open No. H9-288687, for example. In Japanese Patent Application Laid-Open No. H9-288687, it has been described that the time for hierarchical processing can be thereby shortened. However, by the method described in Japanese Patent Application Laid-Open No. H9-288687, although the generation time of photomask drawing data or photomask inspection data can be shortened, this does not lead to a generation of data to be feed back to the above-mentioned drawing device operation parameters, therefore, operation costs for the entire drawing step cannot be reduced.
FIG. 1 is a flowchart showing an outline of photomask manufacturing process in a conventional system. First, as shown in step S1 of FIG. 1, photomask drawing data 31 for a photomask is charged into manufacturing (trial manufacturing). This photomask drawing data 31 is supplied for a drawing analysis step shown in step S21 and an inspecting data conversion step shown in step S22, respectively.
Results of a drawing analysis obtained in the drawing analysis step of step S21 are feed back to a drawing step shown in step S3, which is a following step, then photomask drawing is carried out. After drawing, as shown in step S4, post-steps such as processings and an inspection and measurement of the drawn photomask are carried out.
In addition, in the inspecting data conversion step shown in step S22, which is a completely different step from the drawing analysis step shown in step S21, DB inspection data 43 for an inspection apparatus is obtained. Thereafter, as shown in step S5, a DB (Die-to-Database) inspection is applied to the photomask pattern by use of the inspection data 43. The DB inspection means a defect inspection carried out by comparing the photomask pattern with the inspection data 43.
Next, as shown in step S6, a delivery judgement is carried out based on inspection results of step S5. As such, the drawing data 31 charged into manufacturing is separately supplied for the drawing analysis step (step S21) and inspecting data conversion (step S22), and the respective steps uniquely carry out processings.
However, the above-described conventional technique has the following problems. In the conventional photomask manufacturing method shown in FIG. 1, since the drawing analysis step and the inspecting data conversion step independently exist, it is necessary to separately control the respective steps. Accordingly, if a single operator controls both steps, an operation time obtained by adding operation times of both steps is required, while if both steps are carried out in parallel, two operators are required. In either case, operation costs are increased. In addition, generally, drawing data formats have no compatibility between different drawing apparatuses, steps according to respective drawing data formats are required, therein a problem exists.
In addition, since the same drawing data is separately analyzed in two steps, an excessive time is required for the analysis itself. In the inspecting data conversion step, from the nature of comparing an observed photomask image with inspection data, it is necessary to interpret drawing data to convert formats to data closer to the observed photomask image. On the other hand, in the drawing data analysis step, as well, since it is necessary to obtain an image after drawing, that is, an observed photomask image, it is necessary to interpret drawing data to obtain data close to the observed image. In the conventional photomask manufacturing method, since these similar processings are separately executed completely independently, the operation time occurs doubly. In addition, since the types of drawing data are dependent on drawing apparatuses, a large number of drawing data formats are generated. And, as the number of drawing data formats increases, the types of operations are increased in respective steps.